Figure 1.

Effect of diabetes on infarct size and cardiomyocyte cell death in humans and mice. (A) Measurement of infarct size (IS) as a percentage of the left ventricle (LV), assessed by MRI one month post-MI in patients (155 non-diabetics vs. 22 diabetics). p = ns. (B) Study design of the diet groups SD and HFHSD together with the oral gavage of Metformin (MET) or Vehicle for the last six weeks of feeding. (C) in vivo model of myocardial infarction in mice consists in 45 min of ischemia induced by ligation of the left descending coronary artery followed by 24 h of reperfusion before assessment of infarct size. Representative images of infarct size are depicted for each group. (D) Measurement of the area at risk (AR/LV), expressed as a percentage of area at risk (AR) over left ventricle (LV), and of the infarct size (AN/AR), calculated as a percentage of area of necrosis over (AN) area at risk. n = 9 SD and 8 HFHSD, *p < 0.05. (E) Timeline of the hypoxia-reoxygenation protocol: hypoxia is induced for 70 min at 0.5% O₂ followed by reoxygenation at 19% O₂ for 2 h before assessment of cell death. (F) Representative images of combined white light and propidium-iodide (in blue) cardiomyocytes from SD, HFHSD, and HFHSD+MET mice, in normoxic condition (TC) and after hypoxia-reoxygenation (HR). (G) Assessment of cell death by propidium iodide (PI) staining after hypoxia-reoxygenation in cardiomyocytes from SD, HFHSD, and HFHSD+MET mice (n = 4-5/group). *p < 0.05.